TECHNICAL FIELD
[0001] This document discloses a four point link suspension for a vehicle, sometimes referred
to as a parallelogram wheel suspension. A vehicle is also described, comprising the
four point link suspension.
BACKGROUND
[0002] A common rear air suspension type utilised in vehicles is a parallelogram suspension
with four air springs. Typically, two air springs are positioned in front of the rear
wheel axle and two air springs positioned in rear of the wheel axle. This arrangement
is sometimes referred to as a 4-bellow suspension unit.
[0003] The bellow suspension unit substantially defines the shape of a parallelogram to
control and stabilise the axle. Due to this arrangement, the caster of the axle can
remain virtually constant as the axle moves vertically with respect to the chassis.
[0004] Often these types of 4-bellow suspension units have a v-rod with a central position
at the top of the rear axle and inside of the chassis frame side members in connection
with (or in close connection with) via a cross-member placed at the frame outside
mounted rod brackets.
[0005] Usually, an anti-roll bar function is either integrated into the lower torque rods
or separately with an anti-roll bar apart from the rod brackets. There may also be
provided anti-roll bar or stabiliser solutions which are integrated in an X or H shape
type of rod and are placed in the same way in the chassis as a v-rod.
[0006] An anti-roll bar is configured to only handle rolling loads while a stabiliser rod,
which also may be referred to as a stabilink or stabilenkers, are configured to handle
rolling loads as well as longitudinal loads and lateral loads.
[0007] When combining this suspension type with an e-axle design, which has its drive unit
directly mounted on the front part of the axle, it is problematic to get it to fit
between the front air springs. Particularly when considering dynamic movements of
the rear axle.
[0008] The e-axle, or e-drive, combines an electric vehicle's gear, motor, and power-control
electronics in one compact unit at the axle of battery-electric vehicles/ hybrid vehicles.
[0009] There are solutions on the market that uses a parallelogram rear air suspension (nonreactive
suspension) described above, but with a design that uses two rear mounted air springs
only and thus enables more space for a drive unit mounted at the front of an e-axle.
[0010] These solutions often use a stabiliser bar or beam constituting both torque rod and
stabiliser functions as well as carrying the vertical load from the air springs.
[0011] A problem with these solutions is that the stabilising function is very roll stiff
and does not allow the lateral movement a high positioned roll centre imposes.
[0012] This can have a negative impact on mobility (traction), vehicle comfort and handling.
[0013] It is thus desired to achieve further developments for improving vehicle driving
behaviour and comfort onboard the vehicle during transportation.
SUMMARY
[0014] It is therefore an object of this invention to provide an improved suspension for
a vehicle, and a vehicle comprising an improved suspension.
[0015] According to a first aspect of the invention, this objective is achieved by a four
point link suspension for a vehicle. The four point link suspension comprises a first
side suspension spring, configured to absorb a vertical load and a second side suspension
spring, configured to absorb the vertical load; wherein the first side suspension
spring and the second side suspension spring are configured to be connected to a vehicle
frame of the vehicle. The four point link suspension also comprises a stabilisation
frame, which comprises a first side link arm having a first ending comprising a first
joint to a first side vehicle frame and a second ending connected to the first side
suspension spring via a second joint. The stabilisation frame also comprises a second
side link arm having a first ending comprising a first joint for connecting a second
side vehicle frame and a second ending connected to the second side suspension spring
via a second joint. The stabilisation frame furthermore comprises a torsion bar, connecting
the first side link arm and the second side link arm.
[0016] Each of the first side link arm and the second side link arm is tapered towards the
respective first ending.
[0017] Thanks to the described aspects, by tapering the side link arms towards the respective
first ending, various lateral and twisting movements are managed better than according
to prior art solutions. Thereby an improved vehicle suspension is achieved, having
conditions for a reduced transfer of forces and vibration caused by undulations in
the road surface, such as bumps or corrugations, to the vehicle frame and thereby
also to the driver, passengers and/ or cargo, which provides conditions for an enhanced
comfort for driver and/ or passengers of the vehicle during propulsion.
[0018] In case the vehicle is transporting cargo, the improved vehicle suspension may prevent
the cargo from dislocation (which may cause a traffic accident) and/ or from becoming
damaged. In case the vehicle is transporting passengers, such as a public transportation
vehicle/ bus, the improved vehicle suspension may prevent passengers from falling
and/ or hurting themselves.
[0019] A smooth and convenient vehicle suspension also provides ergonomical advantages for
the driver, leading to elimination or at least reduction of musculoskeletal disorder
of the driver, and generally to a safer vehicle. Driver fatigue on long journeys may
be eliminated or at least reduced, which improves traffic safety.
[0020] The improved vehicle suspension may also enable the driver to pass curves and road
irregularities at higher speed than otherwise, yet being in full control of the vehicle,
thereby reducing transportation time of the vehicle to the destination.
[0021] Optionally, the tapering towards the respective first ending of the first side link
arm and the second side link arm may comprise reduction of a vertical extension dimension
of the side link arms, from a first vertical extension dimension at the respective
second ending of the first side link arm and the second side link arm, to a second
vertical extension dimension at the respective first ending of the first side link
arm and the second side link arm. The second vertical extension dimension may be within
a range of 40-90 % of the first vertical extension dimension, or within a range of
50-80 % of the first vertical extension dimension.
[0022] By reducing the vertical extension dimension of the side link arm towards the second
ending of the side link arms, the suspension properties of the four point link suspension
is further improved.
[0023] Optionally, the side link arms may comprise a respective connection arrangement configured
to connect a vehicle axle of the vehicle to the side link arms. A first distance between
the respective side link arms at the connection arrangement may be longer than a second
distance between the respective side link arms at the first ending of the side link
arms.
[0024] An advantage by the provided design of the side link arms is that side movements
and twisting movements that an axle roll with a high roll centre imposes. Also, under-steering
behaviour of the vehicle comprising the suspension is increased, leading to improved
driving properties due to calm and predictable driving behaviour of the vehicle during
propulsion.
[0025] Optionally, the second distance may be within a range of 70-99 % of the first distance,
or within a range of 90-97 % of the first distance, as has been observed by the inventors
as particularly advantageous when it comes to suspension and under-steering behaviour
of a vehicle comprising the four point link suspension.
[0026] Optionally, the tapering towards the respective first ending of the first side link
arm and the second side link arm may comprise reduction of a lateral extension dimension
of the side link arms, from a first lateral extension dimension at the respective
second ending, to a second lateral extension dimension at the respective first ending,
wherein the second lateral extension dimension is shorter than first lateral extension
dimension.
[0027] By reducing the lateral extension dimension of the respective side link arms towards
the respective second ending, an enhanced flexibility, i.e., improved capacity for
lateral movements is achieved, which enable an improved handling of lateral and twisting
movements of the suspension. Thereby, also the driving properties of the vehicle comprising
the suspension are improved.
[0028] Optionally, the second lateral extension dimension may be within a range of 10-50
% of the first lateral extension dimension, or within a range of 20-40 % of the first
lateral extension dimension. These intervals have been concluded to be in particular
advantageous by the inventors when it comes to improvement of driving properties of
the vehicle comprising the suspension.
[0029] Optionally, the second vertical extension dimension at the first ending of the side
link arms may be longer than the second lateral extension dimension at the respective
first ending of the side link arms.
[0030] Hereby, the side link arms are enabled the suspension to handle and absorb heavy
vertical loads, while enabling suspension of rolling/ twisting movements by lateral
flexibility.
[0031] Optionally, the second vertical extension dimension may be within a range of 200-2
000 %, or within a range of 400-1 000 % of the second lateral extension dimension
of the respective side link arm at the respective first ending. These intervals have
been concluded to be in particular advantageous by the inventors when it comes to
improvement of suspension behaviour during load.
[0032] Optionally, each of the first side link arm and the second side link arm may be configured
to allow lateral movements of the respective side link arms with a distance which
is at least double as long as the second lateral extension dimension of the respective
side link arm at the respective first ending.
[0033] By enabling lateral movement displacements of the side link arms, the capacity of
the side link arms to absorb twisting and rolling movements is improved. Driving properties
of the vehicle are improved and vehicle comfort is enhanced, which in turn may reduce
accident probability. Also, a richer driving experience is provided.
[0034] Optionally, the torsion bar may be extending between a first connection point of
the first side link arm, and a second connection point of the second side link arm.
[0035] Thanks to the introduced torsion bar, twisting and rolling movements of the vehicle
is handled.
[0036] Optionally, the first side suspension spring and the second side suspension spring
may be attached to the respective second ending of the first side link arm and the
second side link arm.
[0037] By attaching the suspension springs at the respective second ending of the side link
arms, close to the torsion bar, vertical loads from the springs are absorbed by the
stabilisation frame via the side link arms.
[0038] Optionally, the connection arrangement of each respective side link arm may comprise
a centre positioned bearing, which may be attached in connection with a connection
means, configured for fixating a vehicle axle of the vehicle to the side link arms.
[0039] It has been observed that vehicle behaviour and suspension properties are improved
by the attachment of the vehicle axle to the stabilisation frame via the centre positioned
bearing.
[0040] Optionally, each of the first side link arm and the second side link arm may be bended
in a vertical extension dimension towards the respective first ending, in relation
to the respective second ending.
[0041] Hereby, space is saved for vehicle components, enabling more space for surrounding
objects such as e.g., a brake cylinder, etc.
[0042] Optionally, each of the side link arms may comprise a first segment comprising the
respective first ending and a second segment comprising the respective second ending,
wherein the respective first segment is extending substantially along a first direction
and the respective second segment is extending substantially along a second direction,
wherein the first direction and the second direction are deviating from each other
with an angle ϕ within a range of 1-20 degrees, or within a range of 5-10 degrees.
[0043] These intervals have been concluded to be in particular advantageous by the inventors
when it comes to improvement of suspension behaviour during load.
[0044] According to a second aspect of the invention, this objective is achieved by a vehicle
comprising a four point link suspension according to the first aspect of the invention,
or any optional embodiment thereof.
[0045] Thanks to the described aspects, the problems of prior art solutions involving parallelogram
rear air suspension are omitted. Instead, a four point link suspension is provided,
having conditions for radically improved properties concerning management of lateral
and twisting movement an axle roll with a high roll centre imposes, thereby improving
comfort onboard the vehicle.
[0046] A compact suspension is hereby obtained capable of providing protection for sensitive
ingoing components as for example the air springs, but also provides space which enable
implementation of an e-axle with a front mounted drive unit.
[0047] Also, under-steer behaviour of the vehicle having the four point link suspension
can be achieved, leading to improved directional stability, such as driving experience
when changing driving lanes etc., in particular when driving in highway speed.
[0048] Other advantages and additional novel features will become apparent from the subsequent
detailed description.
FIGURES
[0049] Embodiments of the invention will now be described in further detail with reference
to the accompanying figures, in which:
- Figure 1
- schematically illustrates a vehicle according to an embodiment of the invention.
- Figure 2A
- illustrates an embodiment of a four point link suspension and a section of a vehicle
frame.
- Figure 2B
- illustrates an embodiment of a four point link suspension and a section of a vehicle
frame.
- Figure 2C
- illustrates an embodiment of a four point link suspension and a section of a vehicle
frame.
- Figure 3A
- illustrates a stabilisation frame of a four point link suspension according to an
embodiment of the invention.
- Figure 3B
- illustrates a stabilisation frame of a four point link suspension according to an
embodiment of the invention.
- Figure 3C
- illustrates a stabilisation frame of a four point link suspension according to an
embodiment of the invention.
- Figure 4A
- illustrates a side link arm of a stabilisation frame according to an embodiment of
the invention.
- Figure 4B
- illustrates a side link arm of a stabilisation frame according to an embodiment of
the invention.
DETAILED DESCRIPTION
[0050] Embodiments of the invention described herein are defined as a four point link suspension
and a vehicle comprising the four point link suspension, which may be put into practice
in the embodiments described below. These embodiments may, however, be exemplified
and realised in many different forms and are not to be limited to the examples set
forth herein; rather, these illustrative examples of embodiments are provided so that
this disclosure will be thorough and complete.
[0051] Still other objects and features may become apparent from the following detailed
description, considered in conjunction with the accompanying drawings. It is to be
understood, however, that the drawings are designed solely for purposes of illustration
and not as a definition of the limits of the herein disclosed embodiments, for which
reference is to be made to the appended claims. Further, the drawings are not necessarily
drawn to scale and, unless otherwise indicated, they are merely intended to conceptually
illustrate the structures and procedures described herein.
[0052] Figure 1 schematically illustrates a vehicle
100 driving on a road segment
110.
[0053] Practicality, performance and comfort of the vehicle 100 are affected by a suspension
arrangement of the vehicle 100, in particular when passing a height irregularity of
the road 100 such as e.g. a speed bump, a sidewalk curb or other object protruding
from the road surface; and/ or a cross road where the cross roads has different inclinations.
However, the height irregularity may also comprise a cavity in the road surface, such
as a hole, or a cluster of holes.
[0054] According to the illustrated embodiments, the vehicle 100 is a truck. According to
further embodiments, the vehicle 100, as referred to herein, may be another type of
heavy or lighter type of vehicle, such as a bus, a lorry, a car, a trailer, or other
similar manned or unmanned means of conveyance running on wheels. In some embodiments,
the vehicle 100 may be driver controlled or driverless (i.e., autonomously controlled)
in different embodiments.
[0055] The illustrated vehicle 100 of Figure 1 has three axles. However, other embodiments
of the vehicle 100 may have a rear bogie axle, two axles, four axles, five axles,
etc. Further, the vehicle 100 may comprise a trailer; and/ or an articulated/ bi-articulated
vehicle 100, etc.
[0056] The vehicle 100 comprises a four point link suspension according to any embodiment
as illustrated in any one of the Figures 2A-4B, and/ or discussed in the corresponding
section of the description.
[0057] Figure 2A illustrates a four point link suspension
200, sometimes also referred to as a parallelogram wheel suspension. The four point link
suspension 200 is intended for usage in a vehicle 100, in particular for a rear wheel
axle of the vehicle 100.
[0058] The illustrations of Figures 2A-2C are depicting examples of how the four point link
suspension 200 according to some embodiments be implemented in the vehicle 100, while
details of the four point link suspension 200 and in particular the therein comprised
stabilisation frame are illustrated in Figures 3A-3C.
[0059] The four point link suspension 200 comprises a first side suspension spring
210a, and a second side suspension spring
210b. The side suspension springs 210a, 210b may comprise air springs/ pneumatic springs.
However, in alternative embodiments, the side suspension springs 210a, 210b may comprise
torsion springs, hydropneumatics springs, coil springs, leaf springs, etc., in different
embodiments.
[0060] The first side suspension spring 210a, and a second side suspension spring 210b are
configured to absorb a substantially vertical load of the four point link suspension
200. The suspension springs 210a, 210b may be height adjustable in some embodiments.
[0061] The first side suspension spring 210a and the second side suspension spring 210b
are configured to be connected to a vehicle frame
220a, 220b of the vehicle 100 for example by an appropriate fastener such as threaded fastener
involving a nut and a bolt, and possibly also involving washers. In other embodiments,
the fastening may be made semi-permanent by means of a rivet, or even permanently
by means of welding, gluing, etc.
[0062] The set of suspension springs 210a, 210b, of the vehicle 100 may comprise any of
the frontal suspension springs of the vehicle 100, and/ or the rear suspension springs
of the vehicle 100, in different embodiments. Possibly in some alternative embodiments,
one separate four point link suspension 200 may be applied for each of the sets of
springs.
[0063] Figure 2B illustrates a four point link suspension 200, as regarded in a side view.
[0064] The first side link arm and the second side link arm of the stabilisation frame are
connected to the vehicle frame 220a, 220b of the vehicle 100, via a first joint and
possibly an extension part of the vehicle frame 220a, 220b, and also connected to
the side suspension springs 210a, 210b. In the illustrated embodiment, the vehicle
frame 220a, 220b comprises two beams arranged parallel to a longitudinal direction
of the vehicle 100.
[0065] In the illustrated embodiment, a respective frontal section of the first side link
arm and the second side link arm of the stabilisation frame are connected to the vehicle
frame 220a, 220b while a rear section of the first side link arm and the second side
link arm are connected via the side suspension springs 210a, 210b to the vehicle frame
220a, 220b.
[0066] Also, the first side link arm is connected to the second side link arm via a torsion
bar, which together are forming the stabilisation frame, as may be seen in
Figure 2C.
[0067] A vehicle axle of the vehicle 100 may be connected to the first and second side link
arms of the stabilisation frame via connection means
240a, 240b connected to the respective side link arms via centre positioned bearing
230a, 230b.
[0068] Figure 3A illustrates a stabilisation frame
300 in an embodiment. The stabilisation frame 300 comprises a first side link arm
310a, a second side link arm
310b and a torsion bar
320, connecting the first side link arm 310a and the second side link arm 310b.
[0069] The first side link arm 310a has a first ending
311a comprising a first joint
312a to the first side vehicle frame 220a. The first side link arm 310a also has a second
ending
313a connected to the first side suspension spring 210a via a second joint
315a, as illustrated in
Figure 3B.
[0070] The second side link arm 310b has a first ending
311b comprising a first joint
312b for connecting a second side vehicle frame 220b. Also, the second side link arm 310b
has a second ending
313b connected to the second side suspension spring 210b via a second joint
315b.
[0071] The first side link arm 310a and the second side link arm 310b are both tapered towards
the respective first ending 311a, 311b.
[0072] The tapering towards the first ending 311a of the first side link arm 310a, and the
first ending 311b of the second side link arm 310b may comprise a reduction of a vertical
extension dimension of the respective side link arms 310a, 310b. The reduction of
the vertical extension dimension of the side link arms 310a, 310b may be made from
a first vertical extension dimension
α1 at the respective second ending 313a, 313b of the first side link arm 310a and the
second side link arm 310b, to a second vertical extension dimension
α2 at the respective first ending 311a, 311b of the first side link arm 310a and the
second side link arm 310b.
[0073] In some embodiments, the second vertical extension dimension α
2 may be within a range of about 40-90 %, or within a range of 50-80% of the first
vertical extension dimension α
1.
[0074] Figure 3C illustrates a stabilisation frame 300 in an embodiment as regarded in a top view.
[0075] The side link arms 310a, 310b of the stabilisation frame 300 may comprise a respective
connection arrangement
316a, 316b. The connection arrangement 316a, 316b may be configured to connect a vehicle axle
of the vehicle 100 to the first and second side link arms 310a, 310b and thereby also
the stabilisation frame 300 and the four point link suspension 200.
[0076] In particular, a rear axle of the vehicle 100 may be connected to the four point
link suspension 200 in some optional embodiments.
[0077] The first side link arm 310a and the second side link arm 310b may be shaped and
positioned in relation to each other, such that a first distance a
1 between the respective side link arms 310a, 310b at the connection arrangement 316a,
316b is longer than a second distance a
2 between the respective side link arms 310a, 310b at the first ending 311a, 311b of
the side link arms 310a, 310b.
[0078] It has been observed that the design of the stabilisation frame 300, wherein the
distance a
2 between the respective side link arms 310a, 310b at the first ending 311a, 311b of
the side link arms 310a, 310b is smaller than the distance a
1 between the respective side link arms 310a, 310b at the connection arrangement 316a,
316b is increasing understeer behaviour, leading to an improved driver experience
of the vehicle 100.
[0079] The second distance a
2 may be within a range of 70-99 %, or within a range of 90-97 % of the first distance
a
1 in order to achieve/ increase the desired understeer behaviour.
[0080] Also, drum brake cylinders and an E-drive unit may utilise the space between the
rear segment of the side link arms 310a, 310b at the connection arrangement 316a,
316b. The e-axle, or e-drive, combines an electric vehicle's gear, motor, and power-control
electronics in one compact unit at the axle of battery-electric vehicles/ hybrid vehicles.
[0081] The tapering towards the first ending 311a of the first side link arm 310a and the
first ending 311b of the second side link arm 310b may also, or in addition comprise
reduction of a lateral extension dimension of the side link arms 310a, 310b. The lateral
extension dimension of the side link arms 310a, 310b may be referred to as thickness
of the side link arms 310a, 310b. The thickness may be tapered from a first lateral
extension dimension β
1 at the respective second ending 313a, 313b, to a second lateral extension dimension
β
2 at the respective first ending 311a, 311b, wherein the second lateral extension dimension
β
2 is shorter than first lateral extension dimension β
1; i.e. the side link arms 310a, 310b may be thinner closer to the respective first
ending 311a, 311b than at the respective second ending 313a, 313b.
[0082] The second lateral extension dimension β
2 may be within a range of 10-50 %, or within a range of 20-40 % of the first lateral
extension dimension β
1.
[0083] The side link arms 310a, 310b may alternatively be referred to as blades. The second
vertical extension dimension α
2, or height, at the first ending 311a, 311b of the side link arms 310a, 310b may be
longer than the second lateral extension dimension β
2, or thickness of the side link arms 310a, 310b at the respective first ending 311a,
311b of the side link arms 310a, 310b.
[0084] The second vertical extension dimension α
2 may in optional embodiments be within a range of 200- 2 000 %, or within a range
of 400-1 000 % of the second lateral extension dimension β
2 of the respective side link arm 310a, 310b at the respective first ending 311a, 311b.
[0085] Each of the first side link arm 310a and the second side link arm 310b may be configured
to allow lateral movements of the respective side link arms 310a, 310b with a distance
which is at least double as long as the second lateral extension dimension β
2 of the respective side link arm 310a, 310b at the respective first ending 311a, 311b.
[0086] The lateral movements, which is enabled by the tapering of the side link arms 310a,
310b, lateral and twisting movements of the vehicle 100 is handled.
[0087] The torsion bar 320 may extend between a first connection point 314a of the first
side link arm 310a, and a second connection point 314b of the second side link arm
310b. The torsion bar 320 may be straight in some embodiments, thereby effectively
transferring torsion movements between the side link arms 310a, 310b. In some embodiments
(as illustrated in Figures 3A-3C), the torsion bar 320 may be somewhat curved backwards
and/ or upwards here so as not to restrict the ground clearance and to move freely
from various components of the vehicle axle.
[0088] The first side suspension spring 210a and the second side suspension spring 210b
may be attached to the respective second ending 313a, 313b of the first side link
arm 310a and the second side link arm 310b via a respective joint 315a, 315b.
[0089] Hereby, vertical load of the vehicle 100 is transferred via the suspension springs
210a, 210b to the stabilisation frame 300. Thus, the torsion bar 320 both provides
a stabilising function as well as carrying the vertical load.
[0090] The connection arrangement 316a, 316b of each respective side link arm 310a, 310b
may comprise a centre positioned bearing 230a, 230b, which may be attached in connection
with a connection means 240a, 240b, configured for fixating a vehicle axle of the
vehicle 100 to the first and second side link arms 310a, 310b.
[0091] Figure 4A and
Figure 4B illustrate different embodiments of the side link arms 310a, 310b. The side link
arm 310 illustrated in Figure 4A is straight yet tapered while the side link arm 310
according to the alternative embodiment illustrated in Figure 4B is bent, e.g., bent-shaped
or banana shaped in a substantially vertical plane. The bending may be made in a vertical
extension dimension of the side link arm 310, towards the respective first ending
311a, 311b, in relation to the respective second ending 313a, 313b.
[0092] Each of the side link arms 310a, 310b may comprise a first segment
401 wherein the respective first ending 311a, 311b may be comprised. Also, each of the
side link arms 310a, 310b may comprise a second segment
402 comprising the respective second ending 313a, 313b of the corresponding side link
arm 310a, 310b.
[0093] The respective first segment 401 of the side link arms 310a, 310b may extend substantially
along a first direction
410 and the respective second segment 402 may extend substantially along a second direction
420.
[0094] In the illustrated embodiment, the first direction 410 and the second direction 420
are deviating from each other with an angle ϕ of approximately in between 5-10 degrees,
or about 7 degrees. According to further embodiments, the first direction 410 and
the second direction 420 may be deviating from each other with an angle ϕ within a
range of 1-20 degrees, or within a range of 5-10 degrees, in some alternative embodiments.
[0095] The side link arms 310a, 310b may comprise a bent section in between the first segment
401 and the second segment 402. In the illustrated embodiment, bent section is bent
with an angle ϕ of approximately about 7 degrees. However, according to further embodiments,
the bent section may be bent with an angle ϕ within the range of 1-20 degrees, or
within the range of 5-10 degrees.
[0096] The terminology used in the description of the embodiments as illustrated in the
accompanying drawings is not intended to be limiting of the described four point link
suspension 200 and/ or vehicle 100. Various changes, substitutions and/ or alterations
may be made, without departing from invention embodiments as defined by the appended
claims.
[0097] The first and second vertical extension dimensions α
1, α
2 may each be measured in a direction parallel to a vertical direction of the vehicle
100 comprising the four point link suspension 200. The vertical direction of the vehicle
100 is perpendicular to a flat horizontal support surface when the vehicle 100 is
positioned in an upright use position onto the flat horizontal support surface. In
other words, the vertical direction of the vehicle 100 is parallel to a surface normal
of the flat horizontal support surface when the vehicle 100 is positioned in the upright
use position onto the flat horizontal support surface. Wheels of the vehicle 100 are
abutting against the flat horizontal support surface when the vehicle 100 is positioned
in the upright use position onto the flat horizontal support surface.
[0098] The vehicle 100 comprises a longitudinal direction. The longitudinal direction is
parallel to the flat horizontal support surface when the vehicle 100 is positioned
in the upright use position onto the flat horizontal support surface. The longitudinal
direction of the vehicle 100 coincides with a forward and reverse driving direction
of the vehicle 100. The vehicle 100 also comprises a lateral direction. The lateral
direction is perpendicular to the longitudinal direction and is perpendicular to the
vertical direction of the vehicle 100. In other words, the lateral direction of the
vehicle 100 is parallel to a flat horizontal support surface when the vehicle 100
is positioned in an upright use position onto the flat horizontal support surface.
[0099] The first and second lateral extension dimensions β
1, β
2 may each be measured in a direction parallel the lateral direction of the vehicle
100 comprising the four point link suspension 200.
[0100] The term "lateral movements" as used herein refers to movements in directions parallel
to the lateral direction of the vehicle 100 comprising the four point link suspension
200.
[0101] The term "vertical load" as used herein refers to a load acting in a direction parallel
to the vertical direction of the vehicle 100 comprising the four point link suspension
200.
[0102] As used herein, the term "and/ or" comprises any and all combinations of one or more
of the associated listed items. The term "or" as used herein, is to be interpreted
as a mathematical OR, i.e., as an inclusive disjunction; not as a mathematical exclusive
OR (XOR), unless expressly stated otherwise. In addition, the singular forms "a",
"an" and "the" are to be interpreted as "at least one", thus also possibly comprising
a plurality of entities of the same kind, unless expressly stated otherwise. It will
be further understood that the terms "includes", "comprises", "including" and/ or
"comprising", specifies the presence of stated features, actions, integers, steps,
operations, elements, and/ or components, but do not preclude the presence or addition
of one or more other features, actions, integers, steps, operations, elements, components,
and/ or groups thereof. The mere fact that certain measures are recited in mutually
different dependent claims does not indicate that a combination of these measures
cannot be used to advantage.
1. A four point link suspension (200) for a vehicle (100), wherein the four point link
suspension (200) comprises:
a first side suspension spring (210a), configured to absorb a vertical load;
a second side suspension spring (210b), configured to absorb the vertical load; wherein
the first side suspension spring (210a) and the second side suspension spring (210b)
are configured to be connected to a vehicle frame (220a, 220b) of the vehicle (100);
a stabilisation frame (300), comprising
a first side link arm (310a) having a first ending (311a) comprising a first joint
(312a) to a first side vehicle frame (220a) and a second ending (313a) connected to
the first side suspension spring (210a) via a second joint (315a);
a second side link arm (310b) having a first ending (311b) comprising a first joint
(312b) for connecting a second side vehicle frame (220b) and a second ending (313b)
connected to the second side suspension spring (210b) via a second joint (315b);
a torsion bar (320), connecting the first side link arm (310a) and the second side
link arm (310b); and
wherein each of the first side link arm (310a) and the second side link arm (310b)
is tapered towards the respective first ending (311a, 311b).
2. The four point link suspension (200) according to claim 1, wherein the tapering towards
the respective first ending (311a, 311b) of the first side link arm (310a) and the
second side link arm (310b) comprises reduction of a vertical extension dimension
of the side link arms (310a, 310b), from a first vertical extension dimension (α1) at the respective second ending (313a, 313b) of the first side link arm (310a) and
the second side link arm (310b), to a second vertical extension dimension (α2) at the respective first ending (311a, 311b) of the first side link arm (310a) and
the second side link arm (310b); wherein the second vertical extension dimension (α2) is within a range of 40-90 %, or within a range of 50-80% of the first vertical
extension dimension (α1).
3. The four point link suspension (200) according to any one of claim 1 or claim 2, wherein
the side link arms (310a, 310b) comprise a respective connection arrangement (316a,
316b) configured to connect a vehicle axle of the vehicle (100) to the side link arms
(310a, 310b), and wherein a first distance (a1) between the respective side link arms (310a, 310b) at the connection arrangement
(316a, 316b) is longer than a second distance (a2) between the respective side link arms (310a, 310b) at the first ending (311a, 311b)
of the side link arms (310a, 310b).
4. The four point link suspension (200) according to claim 3, wherein the second distance
(a2) is within a range of 70-99 %, or within a range of 90-97 % of the first distance
(a1).
5. The four point link suspension (200) according to any one of claims 1-4, wherein the
tapering towards the respective first ending (311a, 311b) of the first side link arm
(310a) and the second side link arm (310b) comprises reduction of a lateral extension
dimension of the side link arms (310a, 310b), from a first lateral extension dimension
(β1) at the respective second ending (313a, 313b), to a second lateral extension dimension
(β2) at the respective first ending (311a, 311b), wherein the second lateral extension
dimension (β2) is shorter than first lateral extension dimension (β1).
6. The four point link suspension (200) according to claim 5, wherein the second lateral
extension dimension (β2) is within a range of 10-50 %, or within a range of 20-40 % of the first lateral
extension dimension (β1).
7. The four point link suspension (200) according to any one of claims 1-6, wherein a
second vertical extension dimension (α2) at the first ending (311a, 311b) of the side link arms (310a, 310b) is longer than
a second lateral extension dimension (β2) at the respective first ending (311a, 311b) of the side link arms (310a, 310b).
8. The four point link suspension (200) according to claim 7, wherein the second vertical
extension dimension (α2) is within a range of 200- 2 000 %, or within a range of 400-1 000 % of the second
lateral extension dimension (β2) of the respective side link arm (310a, 310b) at the respective first ending (311a,
311b).
9. The four point link suspension (200) according to any one of claims 1-8, wherein each
of the first side link arm (310a) and the second side link arm (310b) is configured
to allow lateral movements of the respective side link arms (310a, 310b) with a distance
which is at least double as long as a second lateral extension dimension (β2) of the respective side link arm (310a, 310b) at the respective first ending (311a,
311b).
10. The four point link suspension (200) according to any one of claims 1-9, wherein the
torsion bar (320) is extending between a first connection point (314a) of the first
side link arm (310a), and a second connection point (314b) of the second side link
arm (310b).
11. The four point link suspension (200) according to any one of claims 1-10, wherein
the first side suspension spring (210a) and the second side suspension spring (210b)
are attached to the respective second ending (313a, 313b) of the first side link arm
(310a) and the second side link arm (310b).
12. The four point link suspension (200) according to any one of claims 1-11, wherein
the connection arrangement (316a, 316b) of each respective side link arm (310a, 310b)
comprises a centre positioned bearing (230a, 230b), which is attached in connection
with a connection means (240a, 240b), configured for fixating a vehicle axle of the
vehicle (100) to the side link arms (310a, 310b).
13. The four point link suspension (200) according to any one of claims 1-12, wherein
each of the first side link arm (310a) and the second side link arm (310b) is bended
in a vertical extension dimension.
14. The four point link suspension (200) according to any one of claims 1-13, wherein
each of the side link arms (310a, 310b) comprises a first segment (401) comprising
the respective first ending (311a, 311b) and a second segment (402) comprising the
respective second ending (313a, 313b), wherein the respective first segment (401)
is extending substantially along a first direction (410) and the respective second
segment (402) is extending substantially along a second direction (420), wherein the
first direction (410) and the second direction (420) are deviating from each other
with an angle ϕ within a range of 1-20 degrees, or within a range of 5-10 degrees.
15. A vehicle (100) comprising a four point link suspension (200) according to any one
of claims 1-14, wherein the vehicle (100) comprises a vehicle frame (220a, 220b) configured
to be connected to a first side suspension spring (210a) and a second side suspension
spring (210b) of the four point link suspension (200); and also configured to be connected
to a first side link arm (310a) and aa a second side link arm (310b).